1. Field of the Invention
This invention relates to the field of rigging. More specifically, the invention comprises a load pin for joining two or more mechanical components together. The load pin includes multiple retention features that require two separate motions to unlock the pin.
2. Description of the Related Art
There are many different devices used for locking two or more separate components together. FIG. 1 shows one such device. Anchor 12 is to be joined to loading component 14. In this example, the objective is to provide a pivoting joint between the two components, resulting in pivoting connection 10.
Transverse hole 28 is provided through both anchor 12 and loading component 14. Load pin 16 is passed through this hole. An enlarged head is provided on the opposite side of the pin (not shown in the view). Once the pin is in place, it is generally desirable to provide a feature that retains the pin in position (sometimes referred to as an “anti-backout” feature). In the example shown, Cotter pin 18 is passed through a transverse hole in the exposed portion of load pin 16. The free ends of the cotter pin are then splayed apart in order to retain the cotter pin.
FIG. 2 shows the disassembly of the example of FIG. 1. Cotter pin 18 is straightened and pulled free as shown. Load pin 16 is then pulled clear of transverse hole 28. In this view the reader may easily perceive the function of head 26, which prevents the load pin passing completely through the transverse hole.
FIG. 3 shows another very common prior art fastening device. Shackle 20 is a bow-shaped device including open span 30. The open span must generally be closed in order to encircle the component that is attached to the shackle. Load pin 16 is passed through a transverse hole in the shackle in order to close open span 30. The shackle assembly may then be used to transmit force from one component to another. For example, a first wire rope may be secured around load pin 16 while a second wire rope is secured around the opposite end of shackle 20. Tension may then be transferred between the two wire ropes.
The load pin must generally be secured in position. Head 26 is an enlarged portion that is too big to fit through the transverse hole in the shackle. Once the leading portion of load pin 16 has passed through the shackle, another component is added to prevent its being pulled back out. In the embodiment of FIG. 3, cap screw 22 is passed through an opening through the load pin. Lock nut 24 is then secured on the exposed portion of the threads belonging to the cap screw. With this arrangement, load pin 16 is secured and open span 30 is closed. However, a user wishing to remove the load pin need only unscrew lock nut 24 and pull cap screw 22 free.
The reader will thereby appreciate that the use of a load pin to close an open span in a rigging component is well known. The reader will also appreciate that it is known to secure the load pin in position so that it cannot be easily removed. However, the prior art approach to securing the load pin is cumbersome in both the securing and the removing of the load pin. In addition, the prior art approach includes numerous separate components that may easily be dropped or misplaced during the process. Finally, the prior art approach is time consuming.
Accordingly, it would be advantageous to provide a new approach to selectively securing a load pin that does not require the use of loose components and that is easy and quick to engage and disengage. The present invention provides such a solution.